Method for operating a bin storage system and robot vehicle

ABSTRACT

A method of operating a bin storage system including a plurality of storage columns for the storage of a plurality of vertically-stacked storage bins, and a plurality of robot vehicles for transporting storage bins, the method includes: positioning a cavity of one of the plurality of robot vehicles such that it is aligned with one of the storage columns, receiving a storage bin from the storage column into the cavity, and moving the robot vehicle along the bin storage system, using a plurality of rolling members attached to the vehicle body about the cavity that are arranged for travelling in a first direction and a perpendicular second direction along the bin storage system.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of and, thereby,claims benefit under 35 U.S.C. § 120 to U.S. patent application Ser. No.16/865,443 filed May 4, 2020, which is a continuation of U.S. patentapplication Ser. No. 16/589,158 filed Oct. 1, 2019, which is acontinuation of U.S. patent application Ser. No. 16/122,969 filed Sep.6, 2018, which is a continuation of U.S. patent application Ser. No.15/818,791 filed Nov. 21, 2017, which is a continuation of U.S.application Ser. No. 15/632,441 filed Jun. 26, 2017, which is acontinuation of U.S. patent application Ser. No. 15/411,301 filed Jan.20, 2017, which is a continuation of U.S. patent application Ser. No.15/197,391 filed Jun. 29, 2016, which is a continuation of U.S. patentapplication Ser. No. 14/650,757 filed Jun. 9, 2015, which is a U.S.National Stage of international application PCT/EP2013/075671 filed Dec.5, 2013, which claims foreign priority to Norwegian Patent ApplicationNo. NO 20121488 filed Dec. 10, 2012.

FIELD OF INVENTION

The present invention relates to a remotely operated vehicle for pickingup storage bins from a storage system and a storage system using theinventive vehicle.

A remotely operated vehicle for picking up storage bins from a storagesystem is known. A detailed description of a relevant prior art storagesystem is given in WO 98/49075. Further, details of a prior art vehiclebeing suitable for such a storage system is disclosed in Norwegianpatent NO317366. More specifically the prior art storage systemcomprises a three-dimensional storage grid containing storage bins thatare stacked on top of each other to a certain height. The storage gridis normally constructed as aluminium columns interconnected by toprails. A number of remotely operated vehicles, or robots, are arrangedon the top rails. Each vehicle is equipped with a lift for picking up,carrying, and placing bins that are stored inside the storage grid.

Such a prior art storage system art and prior art robot is illustratedin FIGS. 1 and 2 , respectively. The storage system 3 comprises a robot1 which is arranged to move on dedicated supporting rails 13 and toreceive a storage bin 2 from a storage column 8 within a bin storinggrid 15. The storage system 3 includes a plurality of such robots 1 anda dedicated bin lift device 50, the latter being arranged to receive astorage bin 2 from the robot 1 at the top level of the bin storing grid15 and to convey the storage bin 2 down in a vertical direction to adelivery station 60.

However, the prior art robot 1 shown in both FIG. 1 and FIG. 2 suffersfrom several important disadvantageous during their operation. Firstly,the particular design of the robot prevents access to all off theavailable storage columns in the storage system. Furthermore, thisparticular design may cause an undesirable high torque during liftingand transportation of storage bins, thereby creating potentialinstability problems, as well as a clear limitation of the robotsmaximum handling weight. An additional disadvantage caused by the priorart robot design is the fact that only one particular bin and oneparticular bin height may be accepted for each type of robot in order toensure adequate stability. Finally, the presence of an integratedyoke/overhang in the upper part of the section receiving the storage binnecessitates an undesired speed reduction at the final stage of thelifting process performed by the yoke suspended vehicle lifting device.

SUMMARY

One or more embodiments of the present invention solve, or at leastsubstantially alleviate, the above-described disadvantageous, i.e.,provide a vehicle/robot with higher stability properties, higher maximumhandling weights, a more effective use of available space duringoperation and a less time consuming lifting and transporting process ofstorage bins.

In particular, one or more embodiments of the present invention relateto a remotely operated vehicle or robot for picking up storage bins froma storage system. The inventive vehicle or robot comprises a vehiclebody, which vehicle body further comprises a first section for storingvehicle driving means and a second section for receiving any storage binstored in a storage column within the storage system, a vehicle liftingdevice which is at least indirectly connected to the vehicle body inorder to lift the storage bin into the second section, a first set ofvehicle rolling means connected to the vehicle body in order to allowmovement of the vehicle along a first direction (X) within the storagesystem during use and a second set of vehicle rolling means connected tothe vehicle body in order to allow movement of the vehicle along asecond direction (Y) in the storage system during use. The seconddirection (Y) is oriented perpendicular to the first direction (X).

The inventive vehicle is characterized in that the second sectioncomprises a cavity arranged centrally within the vehicle body. Thiscavity has at least one bin receiving opening facing towards theunderlying storage columns during use. In addition, at least one of thetwo sets of vehicle rolling means is arranged fully within the vehiclebody.

In order to allow easy entrance of the storage bin into the centralcavity, its volume should be larger than the largest storage binintended to be picked from the storage system. Likewise, the crosssectional area of at least one of the at least one bin receiving openingshould be larger than the cross sectional area of the storage bin wallsoriented parallel to the cavity opening(s).

The vehicle may further comprise means for reversibly and selectivelydisplacing either the first set of vehicle rolling means or the secondvehicle rolling means away from an underlying vehicle support within thestorage system during a change of vehicle direction between the firstdirection (X) and the second direction (Y).

Furthermore, in an embodiment the first section may be arranged relativeto the second section in such a way that the cross section of thevehicle parallel to the underlying vehicle support deviates from aquadratic shape.

In a preferred embodiment the vehicle body covers less or equal to thelateral cross sectional area of one central storage column in the firstdirection (X) and covers the lateral cross sectional area of more thanone central storage column in the second direction (Y) during use. In amore specific example the vehicle body extends beyond the lateral crosssectional area of the central storage column at both sides facing thesecond direction (Y), i.e. covering also some of the cross sectionalareas of the adjacent storage columns extending in the second direction(Y). The degree of extension from the central storage column ispreferably equal on both of these sides. Central storage column isdefined as the storage column which is immediately below a robot whenthe latter has reached a position allowing pick-up of a storage bin.

In order to inter alia allow high vehicle stability both sets of vehiclerolling means is preferably arranged symmetrically around the cavity,for example near the lower corners of the vehicle. At least one, andmost preferably both, set(s) of vehicle rolling means may comprise atleast four wheels. Other embodiments such as the use two perpendicularoriented caterpillar belts may be envisaged. Furthermore, both sets havean exterior design matching a corresponding exterior design onsupporting rails constituting the vehicle support in order to provideincreased lateral stability when interconnected. Such supporting railswould be arranged in a two dimensional matrix on top of a bin storingstructure or grid, where the principal directions of both the matrix andthe grid are congruent with the vehicle's first direction (X) and seconddirection (Y).

The vehicle may advantageously also include position sensing means toallow measurements of the vehicle position within the storage systemduring use. This position sensing means may comprise a plurality ofposition sensors arranged in at least some of the positions on thevehicle body which would transverse the locations of vehicle supportwhere the supporting rails are crossing, for example underneath thevehicle, close to its lower corners.

One or more embodiments of the present invention also relates to astorage system which comprises a remotely operated vehicle in accordancewith the above mentioned features, a vehicle support comprising aplurality of supporting rails forming a two dimensional matrix ofguiding meshes, wherein the vehicle support is configured to guide themovements of the vehicle in the first direction (X) and the seconddirection (Y) during use, a bin storing structure or grid supporting thevehicle support comprising a plurality of storage columns, wherein eachof the storage columns is arranged to accommodate a vertical stack ofstorage bins and wherein the main part of the bin storing structurecoincides with positions on the vehicle support where the supportingrails are crossing, and a bin lift device arranged to convey a vehicledelivered storage bin in a direction perpendicular to the lateral planeof the vehicle support between the vehicle support and a deliverystation.

In a preferred embodiment at least some of the supporting rails arrangedat the outer lateral border areas of the vehicle support form outerguiding meshes having reduced average cross sectional areas compared tothe average cross sectional area of the remaining guiding meshes in thevehicle support. For example, the average reduced cross sectional areasof the outer guiding meshes may be about half of the average crosssectional area of the remaining guiding meshes in the vehicle support.In a particularly preferred embodiment these cross sectional areas ofthe outer guiding meshes are reduced only along the second direction (Y)of the vehicle support.

The central arrangement of the cavity in the vehicle body relative tothe second direction (Y) effectively remove the undesired torque,thereby improving the stability of the robot or vehicle. Thisarrangement also results in a lifting and transporting process having aweight distribution with a high degree of symmetry. Furthermore, thenovel design allows the same vehicle to be used for lifting andtransporting storage bins of heights significantly less than the cavityheight (i.e. the height extending from the suspension points of thelifting device and to the lower edge of the vehicle) since theframework/body surrounding at least part of the bin receiving cavityeffectively hinders any undesired bin reeling/wobbling. The presence ofthe cavity surrounding body also allows maintaining full or nearly fulllifting speed almost all the way to its end position within the cavity,as well as initiation of stable bin transportations towards the deliverystation prior to a fully completed bin lifting from a storage column.The protective body around the cavity also gives the possibility ofstarting a descent of the lifting device event prior to the time thevehicle has come to a final halt above the storage column in question. Asignificantly higher stability and time efficiency is thus achieved.

By arranging at least one set of vehicle rolling means fully within thevehicle or robot body additional stability is obtained during thelifting process since the rolling means is situated closer to thestorage bin to be lifted. Of the same reason this arrangement reducesthe total load on the lifting device. Furthermore, the arrangement ismore space efficient relative to the prior art robot illustrated in FIG.2 since the roller means does not give any additional extensions in atleast one of the two robots moving directions (X and Y). Production ofsmaller sized robots/vehicles is also rendered possible.

These and other characteristics of the invention will be clear from thefollowing description of embodiments of the present invention, given asa non-restrictive examples, with reference to the attached drawingswherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a prior art storage system;

FIG. 2 is a sectional view of a prior art robot or vehicle forming partof a storage system as illustrated in FIG. 1 ;

FIG. 3 is a perspective base view of a remotely operated vehicleaccording to the present invention;

FIG. 4 is a perspective top view of a remotely operated vehicleaccording to the present invention;

FIG. 5 is a perspective top view of a robot assembly comprising aremotely operated vehicle according to the present invention, a storagebin and a fully enclosing cover,

FIG. 6 is a perspective top view of a bin storing grid and a vehiclesupport in accordance with the present invention;

FIG. 7 is a perspective side view of a bin storing grid and a vehiclesupport in accordance with the present invention;

FIG. 8 is a perspective side view of part of a storage system inaccordance with the present invention including a bin storing grid, avehicle support and a remotely operated vehicle; and

FIG. 9 is a schematic top view of a remotely operated vehicle moving ona two dimensional matrix of supporting rails.

DETAILED DESCRIPTION

FIG. 1 is a schematic, partly cut perspective view of a storage systemaccording to the prior art, and FIG. 2 is a sectional view of acorresponding prior art robot. Both figures have already been referredto earlier in the text.

FIGS. 3 and 4 gives a perspective view in two different angles of theinventive robot 1 comprising a rectangular vehicle body or framework 4with a cavity 7 centrally arranged within the body 4, a top lid 72covering the top part of the body 4, a first set of four wheels 10mounted inside the cavity 7 and in parallel to the interior walls of thebody 4 and a second set of four wheels 11 mounted in parallel to theexterior walls of the body 4. The first and second set of wheels 10,11are oriented perpendicular to each other. Further, the vehicle body 4also includes side parts 5,5 a,5 b arranged on both sides of the cavity7 along at least one of the robots 1 direction of movements. For thesake of clarity a Cartesian coordinate system is shown with its X, Y andZ axes aligned along the principal directions of the rectangular vehiclebody 4. The size of the cavity 7 is adapted to contain necessarycomponent for a lifting device 9 and to at least completely contain thelargest storage bin 2 intended to be picked up by the robot 1.

FIG. 5 gives a perspective view of a robot assembly where the body 4 iscompletely covered by an enclosing cover 73 comprising handles 74 andtransmission means/control panel 75. The design of the enclosing cover73 is adapted to the particular shape given by the body 4 and theprotruding wheels 10. FIG. 5 also shows a small part of a storage bin 2arranged fully inside the cavity 7 and a small part of the liftingdevice 9. The latter is preferably composed of inter alia fourvertically moveable metal bands suspended on the cavity facing side ofthe top lid 72 in their upper ends and steering rods at the lower endscapable of being steered and fastened into adapted cavities/areas in thestorage bin 2 to be picked.

The structural principles of a grid assembly comprising a bin storingstructure or grid 15, integrated supporting rails 13 constituting thevehicle support 14 and a grid supporting base 76 are illustrated inFIGS. 6 and 7 . The grid 15 comprises a plurality of pillars beingarranged with internal distances adapted to accommodate storage bins 2to be stored in stacks inside the grid 15. The rectangular arrangementsof four adjacent pillars therefore constitute a storage column 8. Boththe pillars and the rails 13 may be made of Aluminium. As for FIGS. 3and 4 a Cartesian coordinate system is shown aligned along the principaldirections of the grid assembly to ease the understanding. Thesupporting rails 13 form a two dimensional matrix of rectangular meshes,and the cross sectional area of most of these meshes coincide with thecross sectional area of each storage columns 8 set up by the underlyinggrid 15. The meshes at the border area 17,18 of the vehicle support 14(at both sides in direction Y) is illustrated with cross sectional areassmaller than the remaining meshes. The size of the border meshes 17,18should preferably be adapted to the degree of extension beyond a centralstorage column 8 a situated immediately below the cavity 7 of the robot1 when the latter is in a position for initiating pick up of a storagebin 2 contained in the central storage column 8 a (see FIGS. 8 and 9 ).In this way the robot 1 may reach all the storage columns 8 in thestorage system 3, i.e. independently of the robot orientation in the Ydirection. For example, if the robot 1 extends exactly over the crosssectional area of one central storage column 8 a in the X direction andover ½ of the cross sectional area of the adjacent storage column 8 b inthe Y direction, the cross sectional area of the meshes 17,18 at theborder area in the Y direction should be approximately ½ of the crosssectional area of the remaining meshes. The primary function of theseborder meshes 17,18 is thus to allow sufficient space for the robot 1having the novel design.

FIG. 8 shows the robot 1 in a lifting position above the central storagecolumn 8 a adjacent to the border area 17,18 of the grid assembly. Thevehicle lifting device 9 is in this embodiment lowered a distance intothe central storage column 8 a in order to hook onto and lift up theunderlying storage bin 2. As seen in the exemplary situation in FIG. 8the robot 1, having the body 4 extended in the Y direction compared tothe X direction, may be driven all the way to the edge of the grid 15when the border area is designed with additional border meshes 17,18with a Y directional width approximately ½ of the Y directional widthsof the remaining meshes in the grid 15.

To better illustrate the movement of the robot 1 on the supporting rails13 constituting the vehicle support 14 some exemplary positions ofrobots 1 on a grid assembly is illustrated in FIG. 9 . The thick arrowsdrawn in the centre of the robots 1 indicate allowed moving directions.When the robot 1 is situated with its cavity 7 exactly above a centralstorage column 8 a, as is the case for the top left and mid centredrobot 1, the arrangement of the supporting rails 13 allow movement inboth X and Y directions. Any other positions on the grid assemblyrestrict the robot's 1 movement on the vehicle support 14 either in Xdirection (lower right robot 1) or in Y direction (top centered andbottom left robot 1). To allow determination of the robot position it isconsidered advantageous to equip each robot 1 with one or more positionsensors 16, for example optical sensors. Such sensors should 16preferably be mounted in one or more areas of the robot 1 which ensuresthat the sensors 16 have both non-obstructed view to the underlyingsupporting rails 13 and that they pass directly above or close to thepositions on the vehicle support 14 in which the rails 13 are crossing.The readings from the sensors 16 may inter alia dictate the furthermovement of the robot 1 and/or the operation of the vehicle liftingdevice 9.

All operations of the robot 1 are controlled by wireless communicationmeans 75 and remote control units. This includes control of the robotmovement, the vehicle lifting device and the position measurements.

In the preceding description, various aspects of the apparatus accordingto the invention have been described with reference to the illustrativeembodiment. For purposes of explanation, specific numbers, systems andconfigurations were set forth in order to provide a thoroughunderstanding of the apparatus and its workings. However, thisdescription is not intended to be construed in a limiting sense. Variousmodifications and variations of the illustrative embodiment, as well asother embodiments of the apparatus, which are apparent to personsskilled in the art to which the disclosed subject matter pertains, aredeemed to lie within the scope of the present invention.

LIST OF REFERENCE NUMERALS/LETTERS

-   1 Remotely operated vehicle/robot-   2 Storage bin-   3 Storage system-   4 Vehicle body/framework-   5 First section (of vehicle body)/component section/side parts-   5 a First section, left-   5 b First section, right-   6 Vehicle driving means/motor unit-   7 Vehicle storage space/second part/cavity/centrally arranged cavity-   8 Storage column-   8 a Central storage column-   8 b Adjacent storage column-   9 Vehicle lifting device-   10 First set of vehicle rolling means/First set of wheels-   11 Second set of vehicle rolling means/Second set of wheels-   12 Bin receiving opening-   13 Supporting rail-   14 Vehicle support-   15 Bin storing structure/grid-   16 Position sensing means/position sensor-   17 Left outer lateral border area of vehicle support/left border    mesh-   18 Right outer lateral border area of vehicle support/right border    mesh-   50 Bin lift device-   60 Delivery station/port-   70 Yoke/overhang-   72 Top lid-   73 Enclosing cover-   74 Handles-   75 Transmission means/control panel/wireless communication means-   76 Grid supporting base

The invention claimed is:
 1. A method of operating a bin storage systemcomprising a plurality of storage columns for storage of a plurality ofvertically-stacked storage bins, and a plurality of robot vehicles fortransporting storage bins, the method comprises: positioning a cavity ofone of the plurality of robot vehicles such that the cavity is alignedwith one of the storage columns, receiving a storage bin from thestorage column into the cavity, and moving the robot vehicle along thebin storage system, using a plurality of rolling members attached to therobot vehicle that are arranged for travelling in a first direction anda perpendicular second direction along the bin storage system.
 2. Themethod according to claim 1, wherein the receiving a storage bin fromthe storage column comprises: descending a lifting device of the robotvehicle into the storage column, engaging a storage bin with the liftingdevice, and lifting the lifting device of the robot vehicle with thestorage bin from the storage column into the cavity.
 3. The methodaccording to claim 1, wherein the cavity is capable of receiving onlyone storage bin at any time.
 4. The method according to claim 1, whereinthe cavity is centrally arranged when viewing from a bottom of the robotvehicle.
 5. The method according to claim 1, wherein the cavity displaysa downwardly facing opening for the storage bin.
 6. The method accordingto claim 1, wherein at least a pair of rolling members are arrangedsymmetrically around the cavity.
 7. A robot vehicle for transportingstorage bins in a bin storage system, comprising: a cavity arranged toreceive a storage bin from a storage column, a plurality of rollingmembers arranged to allow the robot vehicle to travel in a firstdirection and a perpendicular second direction along an underlyingvehicle support of the bin storage system, and means for reversibly andselectively displacing a first set of rolling members and a second setof rolling members away from the underlying vehicle support of thestorage system during a change of vehicle direction between the firstdirection and the second direction.
 8. The robot vehicle according toclaim 7, wherein the cavity is centrally arranged in the robot vehicle.9. The robot vehicle according to claim 7, wherein the cavity displays adownwardly facing opening for the storage bin.
 10. The robot vehicleaccording to claim 7, wherein at least a pair of rolling members arearranged symmetrically around the cavity.
 11. The robot vehicleaccording to claim 7, wherein the bin storage system comprises:three-dimensional storage structure comprising a plurality of pillarswhich are positioned with internal distances and in a rectangulararrangement, wherein the rectangular arrangement of the pillars definethe storage columns for the storage of a plurality of vertically-stackedstorage bins, and supporting rails arranged in a two-dimensional matrixon the pillars, said supporting rails arranged in a first direction anda second direction orthogonal to the first direction, the supportingrails further defining openings for the storage columns.
 12. The robotvehicle according to claim 11, wherein the plurality of rolling membersare arranged for travelling along a plurality of rolling tracks of thebin storage system, and the supporting rails define the rolling tracks.13. A robot vehicle for transporting storage bins in a bin storagesystem, comprising: a cavity arranged to receive a storage bin from astorage column, a plurality of rolling members arranged to allow therobot vehicle to travel in a first and second direction along anunderlying vehicle support of the bin storage system, wherein therolling members, in at least one of the first and second direction, arearranged at an outermost periphery of the robot vehicle, and means forreversibly and selectively displacing a first set of rolling members anda second set of rolling members away from the underlying vehicle supportof the storage system during a change of vehicle direction between thefirst direction and the second direction.
 14. The robot vehicleaccording to claim 13, wherein all components of the robot vehicle,except for the rolling members, do not extend beyond any of the rollingmembers.
 15. The robot vehicle according to claim 13, wherein the cavitycomprises a downwardly facing opening of essentially a same width andlength as the openings for the storage columns.
 16. The robot vehicleaccording to claim 13, wherein a single robot vehicle essentially coversa single opening while retrieving a storage bin, whereby a second robotvehicle traverses an adjacent column unhindered by the first robotvehicle.
 17. A computer program product for a control unit in a binstorage system comprising: a plurality of storage columns for storage ofa plurality of vertically-stacked storage bins, and a plurality of robotvehicles for transporting storage bins, the computer program productcomprises instructions that when executed on the control unit performs amethod of operating the bin storage system, the method comprises:positioning a cavity of one of the plurality of robot vehicles such thatthe cavity is aligned with one of the storage columns, receiving astorage bin from the storage column into the cavity, and moving therobot vehicle along the bin storage system, using a plurality of rollingmembers attached to the robot vehicle that are arranged for travellingin a first direction and a perpendicular second direction along the binstorage system.